In one aspect, thermal energy storage systems are described herein. In some embodiments, such a system includes at least one active thermal storage battery and at least one passive thermal storage battery. The at least one active thermal storage battery includes a container, a heat exchanger disposed within the container, and a first phase change material disposed within the container and in thermal contact with the heat exchanger. The at least one passive thermal storage battery comprises a plurality of thermal storage cells, individual thermal storage cells comprising a container having an interior volume, and a second phase change material disposed within the interior volume of the container.